Many sheet metal parts are produced by bending the sheet metal with a press brake or similar sheet metal forming machine. Press brakes are also sometimes known in the industry as bending brakes, bending presses or pan brakes. Typically, a press brake is a hydraulic press which has a metal die and a metal punch which are shaped to form a particular bend or curve in the sheet metal when the die and punch are pressed together with the sheet metal in-between. Press brakes are available in a wide variety of sizes that range from approximately 1 meter bending length up to 7 meters or more. The different sizes of press brakes can be set up for bending sheet metal parts of different sizes corresponding more or less with the length of the machine. Another technique for utilizing a longer machine is to set up multiple bending stations or stages for bending smaller sheet metal parts along the length of the press brake. The different bending stations can be set up with similar punches and dies for forming a multiplicity of identical parts simultaneously. More advantageously, the press brake can be set up with different punches and dies at each station for progressively forming a complex sheet metal part requiring multiple bending operations.
Whether it is used for bending one large sheet metal part, multiple identical parts or for progressive forming operations, one of the inconveniences of a long press brake is that the press controls, which generally include a foot-operated control pedal and a hand-operated tonnage controller, are not always conveniently accessible to the press brake operator. Typically, the control pedal on these machines is at the end of a long flexible cable so that the pedal can be moved to a convenient position by the operator. The tonnage controller is sometimes mounted on a pedestal above the control pedal so that it can also be moved to a convenient position by the operator. The reality, however, is that the operator's hands are generally occupied with the sheet metal part to be formed so he or she ends up kicking the control pedal along the length of the machine while moving from station to station. This is neither convenient nor efficient. It could also have serious safety consequences if kicking the pedal causes the press to actuate at an inappropriate time or if the operator trips or loses his or her balance while trying to move the control pedal or tonnage controller. It would be desirable, therefore, to provide a way to move the control pedal and/or the tonnage along the length of the press brake from station to station so that it is optimally positioned for convenient use by the press operator at all times.
Some press brakes come equipped with a treadle that spans the front of the machine for operating the brake from any position along its length. This is only a partial solution to the problem because the treadle has a fixed distance away from the front of the press brake. It may be conveniently placed for operating the press while bending small parts, but if the press is used for forming larger sheet metal parts, the operator may have to reach awkwardly forward to the machine with one foot to operate the treadle. A similar inconvenience is experienced by the operator of a hydraulic sheet metal shear when making multiple cuts on a large piece of sheet metal. As the operator makes progressive cuts on the sheet metal, he or she moves closer to the machine while holding the sheet metal part. The optimal control pedal position at the beginning of the operation will be inconvenient by the end of the process and vice versa. If the control pedal is on the end of a flexible cable, the operator will end up pushing or kicking it toward or away from the press or the shear to move it to a convenient operating position. If the machine is equipped with a treadle, it cannot be moved, so it will be awkward to reach whenever large parts are cut or bent. Therefore, it would also be desirable to provide a convenient way to move the controls of a press brake or related sheet metal forming equipment closer or farther away from the machine so that it is optimally positioned for convenient use by the machine operator at all times.